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Power outage and broken circuit?

  1. Jul 3, 2006 #1
    So we had a typical summer lightning storm, and at one point during the storm our power went out. The problem is that after the storm we now have a light in the bathroom that doesn't work, but there is current running to that part of the house because the plugs in there still work. Now I don't really know many details about what makes the power go out, though I know that it's that either the high voltage circuit breaker by the plant is tripped or the local (house) circuit breaker will trip.

    So the design for this light is basically two wires, where I assume that one is the hot wire and one is to ground, and so it looks like whichever is the main wire connects inside to something, which then connects the two bulbs in parallel with conductive plates. Could it be that the circuit breaker didn't work in time and fried the wire connecting the light? I don't think that it has anything to do with the plates because I tried shorting one them to see if it was getting power, but it wasn't.

    Any ideas for trouble shooting? I am just a physicist, and have a limited background in electronics other than the ones I've become accustomed working in a lab (and doesn't help me in this situation), so I'm really lost as to what may have happened.

    P.S. Yes, I flipped all the switches in the circuit breaker back on.
  2. jcsd
  3. Jul 3, 2006 #2


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    Did 'ya try replacing the bulbs?
  4. Jul 3, 2006 #3


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    Just because your plugs still work is no indiction that your lighting circuit is still live, they should be on seperate breakers, find your (breaker box) and, see if all the actuators are all in the up or down possition, if they are all in the same possition (on) then you have a local fault in that rooms electrics,
    it is highly unlikely that the storm burnt out the wireing, if you are careful dismount the switch and check for voltage from switch terminal to ground,
    (mounting box) if you have voltage on both switch terminals (120v)?
    then your problem lies between switch and battern.

    Storms can elect to attack a single poor connection, look for burn marks on both ceiling battern and swich terminals, with the power off remake connections/ renew fitting.
    Last edited: Jul 3, 2006
  5. Jul 4, 2006 #4
    Yes, I flipped all the actuators on. I suppose there must be a local fault then. Would there be a good way about checking voltage other than a DMM?
  6. Jul 5, 2006 #5


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    I'll bump that, since the OP didn't seem to answer. And to the OP, the way that I usually troubleshoot AC Mains problems is to use one of the little plug-in tester deelies. I don't know the technical name for them, but you can buy them at the local hardware store in the electrical section. They have a 3-prong male plug and usually 3 lights on them. When you plug them into an outlet, they light up in a pattern that tells you if you have power, and if it's wired correctly. While you're at the hardware store, you can buy a screw-in male lightbulb to AC Mains female plug adapter, so that you can test the power at the bulb socket. You may need a female 3-prong to male 2-prong power plug adaper as well, since your tester has a male 3-prong plug, and the light bulb adapter thing will have a 2-prong female outlet.

    Do the outlets in the bathroom still have power? Many outlets in bathrooms will have GFCI (ground fault circuit interrupter) protection, and if your light bulb is wired in series with the GFCI circuit, maybe the GFCI has tripped, and neither the outlet nor the bulb have power. If so, just push the "RESET" button on the GFCI outlet.
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